Interpretive Summary: The beetle genus Eleodes includes pest and non-pest species. It is important for pest managers to be able to identify them. The pest species are known as false wireworms and are pests of wheat and other grain crops in the drier areas of the US from the Dakotas to Texas. As a result of this research a new classification is recognized for Eleodes debilis (Omegeleodes). The eleven species classified in the subgenus Melaneleodes are newly defined and illustrated and the characteristics by which they can be recognized are described. The common widespread species, Eleodes carbonarius, is divided into nine subspecies.

Technical Abstract:
The taxonomic history of the genus Eleodes Eschscholtz is reviewed and the subgenus Melaneleodes Blaisdell redefined based on characters of the female terminalia with Blaps carbonaria Say herein designated as type-species. Eleodes debilis LeConte is removed from Melaneleodes to a new monotypic subgenus, Omegeleodes, based on the female characters. The subgenus Melaneleodes as redefined contains eleven species: anthracinus Blaisdell (new status), carbonarius (Say), halli Blaisdell (new status), humeralis LeConte, neomexicanus Blaisdell, parowanus Blaisdell, pedinoides LeConte, quadricollis Eschscholtz, rileyi Casey, tricostatus (Say) and wenzeli Blaisdell. Eleodes halli Blaisdell is resurrected from synonymy as the oldest available name to replace the homonym Eleodes fuscipilosus Blaisdell 1925 (nec Casey 1890). Eleodes anthracinus Blaisdell, a subspecies of E. quadricollis Eschscholtz is elevated to full species. The subspecies E. quadricollis lustrans Blaisdell is placed in a new combination as Eleodes anthracinus lustrans. Eleodes speculicollis Blaisdell is reduced to subspecific status as E. wenzeli speculicollis, new combination. Eleodes reductus Blaisdell is reduced to a subspecies giving a new combination, E. rileyi reductus. Eleodes coloradensis Blaisdell, Eleodes concinnus Blaisdell and Eleodes quadricollis lassenica Blaisdell, are all submerged as synonyms under Eleodes rileyi Casey. A key to the species is provided along with diagnoses for each with notes on distribution and variation. Eleodes carbonarius (Say) is redefined to contain a number of variants previously recognized as species or subspecies. Along with the previously recognized subspecies Eleodes carbonarius carbonarius, Eleodes carbonarius omissus LeConte, E. carbonarius knausi Blaisdell, and E. carbonarius soror LeConte, newly recognized subspecific combinations are: E. carbonarius omissoides Blaisdell and E. carbonarius chihuahuaensis Champion. New subspecies described herein are: Eleodes carbonarius nuevoleonensis and E. carbonarius disjunctus. Eleodes mazatzalensis Blaisdell is placed in synonymy under E. carbonarius carbonarius and Eleodes lineatus Blaisdell is placed in synonymy under E. carbonarius chihuahuaensis Champion. A key for the identification of the nine subspecies of Eleodes carbonarius is provided.